45 CFR § 641.19 - Modification of environmental documents.

---
identifier: "/us/cfr/t45/s641.19"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "45 CFR § 641.19 - Modification of environmental documents."
title_number: 45
title_name: "Public Welfare"
section_number: "641.19"
section_name: "Modification of environmental documents."
chapter_name: "NATIONAL SCIENCE FOUNDATION"
part_number: "641"
part_name: "ENVIRONMENTAL ASSESSMENT PROCEDURES FOR PROPOSED NATIONAL SCIENCE FOUNDATION ACTIONS IN ANTARCTICA"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "E.O. 12114, 44 FR 1957, 3 CFR 1979 Comp., p. 356."
regulatory_source: "57 FR 40339, Sept. 3, 1992, unless otherwise noted."
cfr_part: "641"
---


# 641.19 Modification of environmental documents.

The responsible official should revise or supplement an environmental document if there is a change in a proposed action that may have more than a minor or transitory effect on the antarctic environment, or if there are new circumstances or information that indicate the action may have impacts not anticipated in the original environmental document.